Base with radially movable clamp for detachably mounting stones



April 21, 1964 B. B. BALLANTYNE BASE WITH RADIALLY MOVABLE CLAMP FORDETACHABLY MOUNTING STONES Filed Sept. 25, 1961 MN m N 1%. h;

INVENTOK BYz-zf uafzgr United States Patent C) 3,129,569 BASE WITHRADIALLY MOVABLE CLAMP FOR DETACHABLY MOUNTING STONES Bob B. Ballantyne,Rte. 1, Box 1044, Sandy, Greg. Fiied Se t. 25, 1961, Ser. No. 140,478 3Claims. (CI. 63-29) This invention relates to new and usefulimprovements in jewelry setting structure and more particularly pertainsto a mounting base especially suitable for setting gem stones inbroaches, bracelets, bolo ties and the like.

A primary object of the present invention is to provide a mounting basefor gem stones having improved means for engaging and holding the stonesin a set position.

Another object is to provide a device of the type described whichfacilitates rapid mounting of precious stones.

It is a more particular object of the present invention to provide amounting base for gem stones having resilient means which positivelyclamp the gem stone in position and which have automatic adjustment toaccommodate stones of different size and of varying shapes, andfurthermore to provide a mounting base of the type described having aportion connected to the resilient means and capable of being locked inan over-center, stone holding position merely by rotation thereof.

Briefly stated the present invention is embodied in structure comprisinga body member having a stone supporting surface in which is providedconverging slots. Projecting through these slots are bezels whichcomprise angular extensions of spring arms connected to a common lockingmember rotatably mounted in the body member. The spring arms assume aselected curvature, and the ends thereof opposite their bezel ends areconnected to the rotatable locking member in an off-center arrangementwhereby, upon rotation of the locking member said bezel ends are movedto a closed stone-holding position.

The invention will be better understood and additional objects thereofwill become more apparent from the accompanying specification and claimsconsidered together with the accompanying drawings wherein like numeralsof reference indicate like parts and wherein:

FIGURE 1 is a top plan View of the present mounting base showing thelocking member in its over-center locked position for clamping a stoneon the base;

FIGURE 2 is a side elevational view of the mounting base with partsthereof broken away and showing the locking member in its FIGURE 1position;

FIGURE 3 is a fragmentary bottom plan View of the present device;

FIGURE 4 is a top plan view showing the parts in unlocked or openposition; and

FIGURE 5 is a side-elevational view with parts broken away showing thedevice in its FIGURE 4 position.

Referring particularly to the drawings, the present mounting basecomprises a body member 16 which as best apparent in FIGURES 2 and 5assumes a hollow construction and has a peripheral defining side wall12, a top wall 14 forming a supporting surface for a stone l6, and abottom wall 18 having an upwardly offset portion 20 forming a bottomrecess 22. Offset portion 20 is centrally apertured at 24.

Rotatably mounted in the aperture 24 is a locking member 28 having abottom flange 30 engageable in recess 22.

In a preferred construction, locking member 28 is hollow, having a topwall 32. The parts are arranged such that the bottom surfaces of themembers and 28 are substantially flush. A transverse finger gripping bar34, FIGURE 3, is provided across the bottom of member 28 to facilitatemanual turning thereof.

Attached to the top wall 32 of the locking member 28 are the ends of aplurality of latch arms 36 having bezel or angular portions 38 whichproject through slots 40 in the top wall 14 of mounting base 10. Latcharms 36 comprise fiexible spring elements which may be formed of aspring steel wire and which in a preferred structure assumesubstantially a closed U-shape in their relaxed condition. As will bemore apparent hereinafter, the attached ends of the spring arms arerotatable with the locking member 23 from an unlocked or open position,FIGURE 4, to a locked or closed position, FIGURE 1, these positions ofthe latch arms being shown in dotted lines.

As viewed in side-elevation, FIGURES 2 and 5, the arms 36 have anangular end portion 42 for attachment to the top wall 32 of the lockingmember as by means of an enlarged head or riveted portion 44. Each ofthe spring arms has a generally upwardly curved intermediate portion 46and a substantially straight portion 48 leading into the bezel andengageable with the under surface of top wall 14 to stabilize the bezel.Since the bezels 38 project through the slots 40 and are angular inconstruction, they serve to connect the body member 10 and lockingmember 28 together.

The arms 36 are connected to the locking member 28 in an off-centerposition, i.e., adjacent the peripheral edge whereby upon rotation ofthe locking member the attached end of the arms are carried around thecentral pivot point which for purposes of illustration is designated bythe numeral 50, FIGURE 1. The points of attachment for the arms 36 areassociated with the positioning and spacing of slots 40 in the top wall14 of housing 10, radially outward from the pivot point 50, whereby uponrotating the locking member 28 through approximately degrees the pointsof attachment for the spring arms with the locking member will becarried around to a point such that the pivot axis 50 of the lockingmember is disposed within the spring arms as determined by an imaginarystraight line 52, FIGURE 1, subtending the curve of each arm between thepoint of attachment of the spring arms and their bezels as confined inthe slots. Therefore, since the ends of the spring arms are moved aroundto enclose the axis of the locking member within the springs, anovercenter condition is reached whereby the locking member rather thantending to return to its original position tends to continue itsrotation past the over-center position thereof.

Stop means are employed for limiting rotation of member 28 after it haspassed its over-center position to prevent relaxing of the spring armsby excessive rotation beyond the over-center positon. For this purposeoff-set portion 20 of the bottom wall 18 is provided with an integralupright stop tab 54 and the rotatable locking member 28 has a laterallyprojecting finger 56 adapted for engagement with the said tab in theselected stop position of rotation. Thus, in a stone clamping positionthe spring arms are flexed to maintain the bezels under spring actionand prevent loose mountings of stones. Furthermore, each of the armsmaintains its bezel under spring action in any adjusted position in theslot whereby stones of different sizes and shapes may be clampedsecurely on the body member.

The slots 40 are directed at a specific angle and the bezels 38 are alsospecifically angularly directed relative to the adjacent arm portion 48whereby the bezels will slide freely in the slots as the locking memberapproaches its over-center stopped position and will be biasedsubstantially radially into the stone.

To mount a stone on the device the locking member 28 is rotatedcounter-clockwise to its FIGURE 4 or bezel open position. This is a restposition of the locking member since the curved portion of the springarms abuts the inner surface wall 12 and the ends of these arms cannotmove closer together to rotate the locking member in a counterclockwisedirection. The stone is positioned on the top wall 14 of base 10 andlocking member 28 then rotated. clockwise to its over-center stopposition. In the initial rotation of the locking member toward its stopposition the bezels are drawn radially inward into engagement with thestone. Upon further rotation of the looking member the spring arms areflexed to apply an inward resilient clamping or gripping engagement withthe stone. Upon reaching its stop position the member 28 is locked inposition by over-center action of the springs and will remain in suchlocked position until it is forcefully rotated in the oppositedirection.

It is to be understood that the form of my invention herein shown anddescribed is to be taken as a preferred example of the same and thatvarious changes in the shape, size and arrangement of parts may beresorted to without departing from the spirit of my invention or thescope of the subjoined claims. For example, the slots 40 may assume anydesired length Within the limit of flexibility of springs 36.

Having thus described my invention, I claim:

1. A mounting base for gem stones comprising a base member having asupporting surface for a stone, a locking member-secured rotatably tothe base on the side opposite that of the stone supporting surface, andhaving a center of rotation with respect to said base member andflexible resilient spring clamp arms each respectively secured at oneend to the locking member and having at the other end clamp meansprojecting through one of a plurality of radially elongated slots in thestone supporting surface for engagement with a stone, the slots beingdisposed radially outward from an axis of rotation passing through saidcenter of rotation and said base and the arms being curved about saidaxis of rotation and secured to the locking member at points radiallyoutward from said center and spaced therearound, each said arm defininga line subtending the curve of said each arm between the respectivepoint and slot associated therewith, said base, locking member and armsbeing constructed and arranged so that said locking member is rotatablewith respect to said base member sufficiently to move said arms so thattheir respective subtendiug lines are movable each from a given side ofsaid axis to the other side and so that their respective clamp means aremovable simultaneously radially inward of said center, the spring clamparms being flexed upon rotation of the locking member relative to thebase member in the locking direction to move the clamp means intooverlying engagement with a stone on the stone supporting surface.

2. The mounting base of claim 1 including interengageable stop means onthe base and locking member for limting rotation of the locking memberin said locking direction.

3. The mounting base of claim 1 wherein the clamp means comprise angularprojections which serve to secure the locking member to the base member.

References Cited in the file of this patent UNITED STATES PATENTS385,522 Pierce July 3, 1888 FOREIGN PATENTS 498,154 France Oct. 8, 1919534,458 Canada Dec. 18, 1956

1. A MOUNTING BASE FOR GEM STONES COMPRISING A BASE MEMBER HAVING ASUPPORTING SURFACE FOR A STONE, A LOCKING MEMBER SECURED ROTATABLY TOTHE BASE ON THE SIDE OPPOSITE THAT OF THE STONE SUPPORTING SURFACE, ANDHAVING A CENTER OF ROTATION WITH RESPECT TO SAID BASE MEMBER ANDFLEXIBLE RESILIENT SPRING CLAMP ARMS EACH RESPECTIVELY SECURED AT ONEEND TO THE LOCKING MEMBER AND HAVING AT THE OTHER END CLAMP MEANSPROJECTING THROUGH ONE OF A PLURALITY OF RADIALLY ELONGATED SLOTS IN THESTONE SUPPORTING SURFACE FOR ENGAGEMENT WITH A STONE, THE SLOTS BEINGDISPOSED RADIALLY OUTWARD FROM AN AXIS OF ROTATION PASSING THROUGH SAIDCENTER OF ROTATION AND SAID BASE AND THE ARMS BEING CURVED ABOUT SAIDAXIS OF ROTATION AND SECURED TO THE LOCKING MEMBER AT POINTS RADIALLYOUTWARD FROM SAID CENTER AND SPACED THEREAROUND, EACH SAID ARM DEFININGA LINE SUBTENDING THE CURVE OF SAID EACH ARM BETWEEN THE RESPECTIVEPOINT AND SLOT ASSOCIATED THEREWITH, SAID BASE, LOCKING MEMBER AND ARMSBEING CONSTRUCTED AND ARRANGED SO THAT SAID LOCKING MEMBER IS ROTATABLEWITH RESPECT TO SAID BASE MEMBER SUFFICIENTLY TO MOVE SAID ARMS SO THATTHEIR RESPECTIVE SUBTENDING LINES ARE MOVABLE EACH FROM A GIVEN SIDE OFSAID AXIS TO THE OTHER SIDE AND SO THAT THEIR RESPECTIVE CLAMP MEANS AREMOVABLE SIMULTANEOUSLY RADIALLY INWARD OF SAID CENTER, THE SPRING CLAMPARMS BEING FLEXED UPON ROTATION OF THE LOCKING MEMBER RELATIVE TO THEBASE MEMBER IN THE LOCKING DIRECTION TO MOVE THE CLAMP MEANS INTOOVERLYING ENGAGEMENT WITH A STONE ON THE STONE SUPPORTING SURFACE.